Noise Reduction for Video in Blender
Cycles noise reduction introduced in recently released Blender 2.79 version works exclusively for rendered images because it specifically uses information from the 3D scene to make an educated approximation, as far as I know.

As such it would not work for random video files since no 3D information would be available in most situations

Everything else that uses the Compositor and/or Video Sequence Editor should be able to work as well for externally obtained footage, as long as it does not rely on data obtained from 3D rendering, like render passes, layers, or any other buffered data from a virtual model.

The mentioned addon seems to be used in the node editor as a node group based approach, so in theory it should work with any externally obtained footage.

Just use an Shift+A > Input > Image or Input > Movie clip to insert your video sequence and use the desired nodes as recommended.

Disclaimer: Whether the algorithms or processes used in those nodes will work correctly or satisfyingly in your particular footage or specific type of noise is unknown.

Those nodes were made specifically with Raytracer bound noise/fireflies in mind, that have particularly very high peaks, so it may not work well of the low intensity noise or your particular case.